William Graham Sumner argued that what our conscience tells us depends solely upon our social group. The moral values we hold are not part of our moral nature, according to Sumner. They are part of our training and upbringing. Sumner argued in his book, Folkways: "World philosophy, life policy, right, rights, and morality are all products of the folkways.” In other words, what we perceive as conscience is merely the product of culture upon our minds through childhood training and cultural influence. There are no universal ethical principles, merely different cultural conditioning.

Sumner studied all sorts of societies (primitive and advanced), and was able to document numerous examples of cultural relativism. Although many cultures promoted the idea, for example, that a man could have many wives, Sumner discovered that in Tibet a woman was encouraged to have many husbands. He also described how some Eskimo tribes allowed deformed babies to die by being exposed to the elements. In the Fiji Islands, aged parents were killed.

Sumner believed that this diversity of moral values clearly demonstrated that culture is the sole determinant of our ethical standards. In essence, culture determines what is right and wrong. And different cultures come to different ethical conclusions. Proponents of cultural relativism believe this cultural diversity proves that culture alone is responsible for our morality. There is no soul or spirit or mind or conscience. Moral relativists say that what we perceive as moral convictions or conscience are the byproducts of culture.

The strength of cultural relativism is that it allows us to withhold moral judgments about the social practices of another culture. In fact, proponents of cultural relativism would say that to pass judgment on another culture would be ethnocentric. This strength, however, is also a major weakness. Cultural relativism excuses us from judging the moral practices of another culture. Yet...